For a 40-year-old gadget, it is remarkable what a central role mobile phones continue to play in our lives. April 3 marked the anniversary of Martin Cooper of Motorola becoming the first man to use a mobile in 1973. He says he was lucky not to become the first casualty of mobile phone usage soon after as he walked around talking on it without paying attention to the New York traffic.

From a "brick" that weighed almost a kilogram, cost US$4,000 and had a battery life of four hours, modern mobile phones have come a long way. It is much lighter for the user and on the wallet, though advances in battery life haven't followed that tremendous pace of improvement.

The emergence of smartphones unleashed unforeseen changes and the trend continues. From keeping in touch to doing commerce, mobile phones even changed the very fabric of some societies, as was evident during the Arab spring.

The low cost and easy availability of mobile phones meant that cumbersome and expensive landlines became a thing of the past in many places. According to the UN, more than six billion people have access to a mobile phone now. But only 4.5 billion have access to clean toilets.

Mobile phones have changed our behavioural patterns even without us noticing. Before their advent, a person sitting alone and talking, or walking along the road talking loudly, would have been an extraordinary sight. But now you don't even give a second glance, nor feel odd doing it yourself. Nor do we raise our eyebrows when we see young couples on a date arrive at a restaurant, sit down and not talk. Both will be busy looking at their mobiles. Obviously, some in love can't take their eyes off their ... phones.

One piece of research shows the most common use of mobiles is to check the time.

Even centuries old traditions are now being swept aside by mobile phones. One service offered by agencies on the mainland during the grave-sweeping holiday this week was to arrange for people to go and place flowers on graves of your ancestors for a fee. They would also place a mobile phone there for you to talk to your ancestors. For some people, this year's grave sweeping was just a swipe across the screen.

Alex Lo is on leave

This article appeared in the South China Morning Post print edition as Grave effect of smartphone revolution

I worked for Martin Cooper at Motorola Communications and Industrial Electronics (C&IE) from November 1959 to June 1960. Let me tell you about something I observed on a daily basis at Motorola's plant in Chicago. Motorola C&IE had two black employees. They tended an incinerator on the opposite side of the parking lot from the plant. They were not allowed into the building. And my fellow employees would take their breaks at the second floor windows overlooking that parking lot, and they would make insulting, racist comments about the two black employees.

I went to human relations, and in the most non-confrontational way that I could muster I asked why Motorola did not employ on the basis of ability, without regard to race. And at my six month review, I was terminated.

You don't have to take my word concerning Motorola's employment policies. In September of 1980, Motorola agreed to pay up to $10 million in back pay to some 11,000 blacks who were denied jobs over a seven-year period and to institute a $5 million affirmative action program, according to the federal Equal Employment Opportunity Commission. See the attached PDF file for details.

I have a question for Martin Cooper. Marty, what did you ever do to challenge the blatant, toxic racial discrimination at Motorola?